title: Developmental regulation of phenylalanine hydroxylase activity in Drosophila melanogaster.
abstract: Herein we demonstrate that Drosophila larvae possess a synthetic activity capable of converting phenylalanine to tyrosine. This system is readily extractable and displays many characteristics of phenylalanine hydroxylase systems described in other organisms, the most notable being that a tetrahydropteridine is required for full expression of activity. The level of phenylalanine hydroxylase activity present in the organism varies with the stage of development: from an undetected level of activity at the first larval instar, there is a rapid increase in phenylalanine hydroxylase activity which reaches a peak at the time of puparium formation, after which there is a rapid decrease again to an undetected level.
mesh_terms: D000818:Animals; D004331:Drosophila melanogaster / Q000235:genetics / Q000502:physiology*; D005260:Female; D005786:Gene Expression Regulation; D007814:Larva / Q000201:enzymology*; D008297:Male; D008675:Metamorphosis, Biological; D010649:Phenylalanine; D010651:Phenylalanine Hydroxylase / Q000235:genetics / Q000378:metabolism*; D011679:Pupa / Q000201:enzymology
chemical_list: D010649:Phenylalanine; D010651:Phenylalanine Hydroxylase